Abstract
Blood coagulation factor XIII-A (FXIII-A), a member of the transglutaminase enzyme family, is best known for its fibrin clot stabilizing function during blood coagulation. It possesses amine incorporating and protein crosslinking transamidase activities, but it is also able to cleave the previously formed isopeptide bond by its isopeptidase activity. Our aim was to develop a protein-based assay for better characterization of FXIII-A isopeptidase activity. The first attempt applying the crosslinked D-dimer of fibrin as a substrate was not successful because of poor reproducibility. Then, the principle of an earlier published anisotropy based activity assay was adapted for the measurement of FXIII-A isopeptidase activity. After crosslinking the fluorescently labelled α2-antiplasmin derived peptide and S100A4(GST) lysine donor protein, this protease-resistant γ-glutamyl-ε-lysine isopeptide bond containing protein-peptide product was applied as a substrate for FXIII-A. Using this substrate and detecting decreasing anisotropy, kinetic measurement of FXIII-A isopeptidase activity was achieved at high sensitivity even in a complex biological sample and in the presence of inhibitor.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
